Safety device for hoisting apparatus.



No. 818,523. PATENTED APR. 24, 1906.

Y J. DAHLIN.

SAFETY DEVICE FOR HOISTING APPARATUS.

APPLICATION FILED OCTJB, 1905.

2 SHEETSS HEET 2.

Q (M s mum @526 a wtzawww NITEI) STATES PATENT OFFICE.

SAFETY DEVICE FOR HOlSTlNG APPARATUS.

Specification of Letters Patent.

Patented April 24, 1906.

Application filed October 16. 1905. Serial No. 282.939-

To all whom, it may concern.-

Be it known that I, JOHN DAHLIN, a citizen of the United States, residing at Chisholm, in the county of St. Louis and State of Minnesota, have invented certain new and useful Improvements in Safety Devices for Hoisting Apparatus and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates generally to carriages, cages, or skips that are moved by a cable to a terminal station and should be there stopped each time at the same or approximately the same point to avoid breaking of the cable or other serious damage.

Particularly this invention is designed as a safety device for use in connection with socalled skips or coal-carrying buckets used to elevate coal in mines.

The invention is illustrated in the accompanying drawings, wherein like characters indicate like parts throughout the several views.

Figure 1 is a View in front elevation, with some parts broken away and with some parts indicated by dotted lines, illustrating my invention applied to a coal-hoisting apparatus. Fig. 2 is a vertical section on the line 00 x of Fig. 1; and Figs. 3, 4, and 5 are fragmentary views, principally in front elevation with some parts sectioned, showing the upper portion of the apparatus.

The numeral 1 indicates vertical guidebeams, which at their upper ends are shown as tied together by transverse beams 2.

The numeral 3 indicates the frame portion of the carriage, cage, or skip, and the numeral 4 indicates the basket, skip, or bucket, which, as shown, is pivotally connected to the said traveling frame 3 and is indicated by dotted lines only. The sides of the frame 3 are channeled and slide upon the guide-timbers 1, and at their upper ends they are rigidly tied together by a hollow transverse beam 5. In ordinary construction the hoisting-cable 6 would be permanently attached directly to the transverse tie-beam 5 of the traveling carriage-frame.

In carrying out my invention I attach a coupling-head 7 to the depending end of the cable and provide seats or perforations in the upper and lower plates of the hollow beam 5 to receive the same. In its sides the coupling-head 7 is formed with notches 7, that are adapted to be engaged by coupling-dogs 8, pivotally supported within said hollow beam 5. These coupling-dogs 8 are connected by links 9 to trip-levers 10, the free ends of which project upward, and are provided at their free upper ends with cam-surfaces 10? Normally the coupling-pawls 8 are positively locked into engagement with the coupling head 7 by lock-dogs 11, rigidly secured on short shafts 12, pivoted in the hollow beam 5 and provided at their outer ends with upturned crank portions 12*. The locking positions of the dogs 11 are shown in Fig. 5 and the releasing positions thereof are shown in Figs. 3 and 4.

Working pivotally through seats 13, cut in the vertical guide-beams 1, are strong cagelatches 14, that are yieldingly pressed inward by springs 15 and are adapted to engage un der the ends of the hollow tie-beam 5 to support the carriage-frame 3 in an elevated position, as shown in Fig. 3. In line with the latches 14, but higher up in the guide-beams 1, are trip-lugs 16. 'The latches 14 and the trip-lugs 16 lie in the path of movement of the cam ends 10 of corresponding trip-levers 10; but the said cam-lugs are located so far above the latches 14 that they will not come into engagement with the ends of said triplevers until slightly after the latches 14 have sprung under the ends of the beam 5. Bigidly secured to one of the tie-beams 2 is a trip-plate 17, that depends therefrom and is provided with beveled edges 17. The beveled edges 17 are so disposed that when the skip and the carriage or frame 3 are moved upward, approximately asshown in Fig. 3, the cranks 12" will strike therespective beveled edges 17 and will be forced outward, thereby moving the lock-dogs 11 into releasing positions. When the carriage has been moved slightly farther upward, as shown in Fig. 4, the cam ends 10" of the trip-levers 10 come into engagement with the trip-lugs 16, and thereby move the coupling-dogs 8 into releasing positions, and thereby releasing the coupling-head 7, and hence the cable, from the carriage-frame and skip. This of course prevents breaking of the cable, and the carriage thus released will drop slightly until its IIO tions by engagement of the cranks 12 with the trip plate 17 immediately after the latches 14: are sprung under the ends of the beam and immediately before the cam ends of the levers are brought into engagement with the trip-lugs 16. Under upward movements of the carriage-frame the cam ends of the levers 10 at a time when they are locked against movement by the lock-dogs 11 are thrown against the latches 14 and simply press the latter outward to permit the said levers to pass.

In practice it will of course be the intention to stop the carriage, skip, or other car- 'rier at a point where the several emergency or safety devices will not be brought into action, such a position being indicated in Fig. 1. Hence ordinarily the hoisting apparatus will be used in the usual way and as if the safety devices were not applied. The safety devices, however, prevent breakage or other accidents when the engineer or operator fails to bring the carriage or skip to a stop at the proper point. This safety device, while of small cost, makes it practically impossible to do any damage by a failure to shut off the engine at exactly the proper time. Very many serious accidents have been caused, resulting both in the loss of life and money, due to carelessness of the engineer or operator in stopping of the engine ust at the proper time to prevent the carriage, cage, or skip from being thrown against the overhead work or the fixed structure. To all persons familiar with this subject the importance of my safety device will be readily apparent.

What I claim, and desire to secure by Letters Patent of the United States, is as follows:

1. The combination with upright guides, of a carriage-frame movable thereon, and a cable for raising and lowering said frame, a coupling detachably connecting said cable to said frame, a movable lock normally holding the parts of said coupling interlocked, means for moving said lock into a releasing position when said frame passes a predetermined point, and means for positively separating the parts of said coupling under the upward movement of the said frame and at a time after said lock has been released, substantially as described.

2. The combination with upright guides, of a carriage-frame movable thereon, and a cable for raising and lowering said frame, a coupling detachably connecting said cable to said frame, movable locks normally holding separable coupling uniting said cable to said.

carriage-frame, a lever, and a link connecting said lever to the movable part of said coupling, and a trip located on one of said guides in the path of movement of one of the levers of said tripping connection, operative to effect the release of said cable from said carriage-frame, when the latter reaches a predetermined altitude, substantially as described.

4. The combination with upright guides, of a carriage-frame movable thereon, and a cable for raising and lowering said frame, a coupling detachably connecting said cable to said frame, a movable lock normally holding the parts of said coupling interlocked, means for moving said lock into a releasing position when said frame passes a predetermined point, means for positively separating the parts of said coupling under the upward movement of the said frame and at a..time after said lockhas been released, and a latch for securing said frame against downward movement just before said lock has been released, substantially as described.

In testimony whereoi I affiX my signature in presence of two witnesses.

JOHN DAHLIN.

Witnesses:

THOMAS F. BRADY, JAMES FITZGERALD. 

